Liquid crystal display module and assembling method thereof

ABSTRACT

A liquid crystal display module and an assembling method thereof are disclosed. The liquid crystal display module includes a panel guide for supporting a liquid crystal panel, the panel guide including a first fastening portion, support side members for holding opposite sides of a lamp irradiating light to the liquid crystal panel, respectively, each of the support side members including a second fastening portion having a foreign substance shield, and a bottom case including a third fastening portion having a case hole formed through a side surface of the bottom case, to receive the foreign substance shield.

The present patent document is a divisional of U.S. patent applicationSer. No. 12/265,856, filed Nov. 6, 2008 now U.S. Pat. No. 7,929,075,which claims priority to Korean Patent Application No. P2007-115240filed in Korea on Nov. 13, 2007, which is hereby incorporated byreference.

BACKGROUND

1. Field of the Invention

The present invention relates to a liquid crystal display module, andmore particularly, to a liquid crystal display module and an assemblingmethod thereof which are capable of simplifying an assembling processfor the liquid crystal display module while preventing foreign substancefrom entering the interior of the liquid crystal display module uponfastening screws to the liquid crystal display module.

2. Discussion of the Related Art

With the progress of an information-dependent society, the demand forvarious display devices has increased. To meet such a demand, effortshave recently been made to research flat panel display devices such asliquid crystal display (LCD) devices, plasma display panels (PDPs),electro-luminescent display (ELD) devices, vacuum fluorescent display(VFD) devices, and the like. Some types of such flat panel displaydevices are being practically applied to various appliances for displaypurposes.

In particular, LCDs have been used as a substitute for cathode ray tubes(CRTs) in association with mobile image display devices because LCDshave advantages of superior picture quality, lightness, thinness, andlow power consumption. Thus, LCDs are currently most widely used.Various applications of LCDs are being developed in association with notonly mobile image display devices such as monitors of notebookcomputers, but also monitors of TVs to receive and display broadcastingsignals, and monitors of laptop computers.

Generally, an LCD device includes a liquid crystal display module orLCM, and a driving circuit for driving the liquid crystal displaymodule.

The liquid crystal display module includes a liquid crystal panel, and abacklight unit for irradiating light to the liquid crystal panel. Theliquid crystal display module also includes top and bottom casesdefining a space for receiving the backlight unit and liquid crystalpanel.

The liquid crystal display module further includes a panel guideenclosing respective edges and respective side surfaces of a diffusionplate and a plurality of optical sheets, which are included in thebacklight unit, and a support side member enclosing opposite ends oflamps included in the backlight unit. The panel guide and support sidemember are fastened to the bottom case by screws.

In detail, the support side member is fastened to the bottom case, andthe panel guide is then fastened to both the bottom case and the supportside member fastened to the bottom case. In this case, accordingly, afastening process needs to be carried out twice. In the fasteningprocess, insert nuts are also used. This increases the cost.Furthermore, a metallic foreign substance, which may be formed duringthe screw-fastening process, may enter the interior of the liquidcrystal display module. The metallic foreign substance may generate anelectrical short circuit with a printed circuit board mounted in theliquid crystal display module.

BRIEF SUMMARY

A liquid crystal display module comprises: a panel guide for supportinga liquid crystal panel, the panel guide including a first fasteningportion; support side members for holding opposite sides of a lampirradiating light to the liquid crystal panel, respectively, each of thesupport side members including a second fastening portion having aforeign substance shield; and a bottom case including a third fasteningportion having a case hole formed through a side surface of the bottomcase, to receive the foreign substance shield.

In another aspect of the present invention, a method for assembling aliquid crystal module comprises: preparing a panel guide for supportinga liquid crystal panel, the panel guide including a first fasteningportion, support side members for holding opposite sides of a lampirradiating light to the liquid crystal panel, respectively, each of thesupport side members including a second fastening portion having aforeign substance shield, and a bottom case including a third fasteningportion having a case hole formed through a side surface of the bottomcase, to receive the foreign substance shield; aligning the panel guide,the support side members, and the bottom case such that the first tothird fastening portions overlap; and fastening the first to thirdfastening portions by screws, and inserting the foreign substance shieldinto the case hole.

With the disclosed structure and method, the assembling process can besimplified because the panel guide, support side members, and bottomcase are fastened at one time by screws or the like. Also, it ispossible to prevent metallic foreign substance formed during thefastening of the screws from entering the interior of the liquid crystaldisplay module, and thus to prevent printed circuit boards from beingshort-circuited by metallic foreign substance because the foreignsubstance shield is fitted in the case hole of the bottom case.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andalong with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 is an exploded perspective view schematically illustrating aliquid crystal display (LCD) device according to an exemplary embodimentof the present invention, which includes a backlight unit;

FIG. 2 is an exploded perspective view for explaining a fasteningprocess for a panel guide, support side members, and a bottom case; and

FIG. 3 is a cross-sectional view taken along the line I-I in FIG. 2,illustrating the fastened panel guide, support side members, and bottomcase.

DETAILED DESCRIPTION OF THE DRAWINGS AND THE PRESENTLY PREFERREDEMBODIMENTS

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

Hereinafter, a liquid crystal display module and an assembling methodthereof according to an exemplary embodiment of the present inventionwill be described with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view schematically illustrating aliquid crystal display (LCD) device according to an exemplary embodimentof the present invention, which includes a backlight unit.

The LCD device shown in FIG. 1 includes a liquid crystal panel 100 fordisplaying an image, and a backlight unit 2 for supplying light to theliquid crystal panel 100. The LCD device also includes a top case 130and a bottom case 10, which receive the liquid crystal panel 100 andbacklight unit 2.

The top case 130 has a bent structure to enclose a non-display area ofthe liquid crystal panel 100 and side surfaces of the bottom case 10.The top case 130 is fastened to a panel guide 90, which encloses theside surfaces of the bottom case 10.

The liquid crystal panel 100 is seated on the panel guide 90. The liquidcrystal panel 100 controls the transmittance of light supplied from thebacklight unit 2 in accordance with an input image signal, to display animage. The liquid crystal panel 100 includes a lower substrate 102, anupper substrate 104, a liquid crystal layer (not shown) formed betweenthe lower substrate 102 and the upper substrate 104, and spacers (notshown) for maintaining a certain spacing between the lower substrate 102and the upper substrate 104.

The upper substrate 104 includes color filters, a black matrix, andcommon electrodes.

The lower substrate 102 includes thin film transistors, and pixelelectrodes respectively connected to the thin film transistors. Thecommon electrodes, which are provided at the upper substrate in theillustrated case, may be formed at the lower substrate 102 in accordancewith a liquid crystal mode different from that of the illustrated case.

Formed on the non-display area of the lower substrate 102 are data padareas respectively connected to data lines (not shown) and gate padareas respectively connected to gate lines (not shown). A plurality ofdata circuit films 110, on which data integrated circuits 112 aremounted to supply image signals to the data lines, are attached to thedata pad areas, respectively. A plurality of gate circuit films 120, onwhich gate integrated circuits 122 are mounted to supply gate scansignals to the gate lines, are attached to the gate pad areas,respectively.

Otherwise, the data integrated circuits 112 and gate integrated circuits122 may be directly mounted on the lower substrate 102 in accordancewith a chip-on-glass (COG) method, or may be formed together with thethin film transistors of the lower substrate 102 such that they arebuilt in the lower substrate 102.

The backlight unit 2 includes a plurality of lamps 40 each having firstand second electrodes 42 and 44, a first socket unit including aplurality of first sockets 22 connected to respective first electrodes42 of the lamps 40, and a second socket unit including a plurality ofsecond sockets 32 connected to respective second electrodes 44 of thelamps 40. The backlight unit 2 also includes a diffusion plate 70arranged beneath the panel guide 90 such that the diffusion plate 70faces the lamps 40, at least one optical sheet 80 arranged on thediffusion plate 70, a first support side member 50 arranged at one sideof the bottom case 10, to enclose the first socket unit and one end ofeach lamp 40, and a second support side member 60 arranged at the otherside of the bottom case 10, to enclose the second socket unit and theother end of each lamp 40.

The diffusion plate 70 diffuses light irradiated from the lamps 40 overthe entire region of the liquid crystal panel 100.

The optical sheet 80 functions to cause the light diffused by thediffusion plate 70 to be vertically irradiated to the liquid crystalpanel 100. To this end, the optical sheet 80 may include at least oneprism sheet for condensing the light diffused by the diffusion plate 70.In the illustrated case, the optical sheet 80 includes two prism sheets82 and 84.

The first and second socket units are arranged on first and secondprinted circuit boards (PCBs) 20 and 30, respectively. Each of the PCBs20 and 30 is provided with a common line to supply a lamp drivingvoltage.

The lamps 40 are separably mounted between the sockets 22 and 32respectively mounted on the first and second PCBs 20 and 30 such thatthe lamps 40 face the liquid crystal panel 100. Each lamp 40 may be acold cathode fluorescent lamp (CCFL). Each lamp 40 is turned on by alamp driving voltage supplied from the associated sockets 22 and 32, toirradiate light to the liquid crystal panel 100.

Although not shown, a lamp tube, in which phosphors emit light inaccordance with gas discharge, or an external electrode fluorescent lamp(EEFL), in which electrodes are arranged on an outer surface of a lamptube body at opposite ends of the lamp tube body, may be used for eachlamp 40. In this case, the structure of each socket may be changed.

The panel guide 90 is mounted on a seat portion of the bottom case 10such that the panel guide 90 can enclose not only the edges and sidesurfaces of the diffusion plate 70 and optical sheets 80, but also theside surfaces of the bottom case 10. The panel guide 90 also functionsto support the liquid crystal panel 100, to prevent the backlight unit 2from moving, and to absorb external impact applied to the backlight unit2.

The bottom case 10 is manufactured to have a bottom surface facing thelamps 40, and inclined surfaces upwardly inclined from the bottomsurface by a certain inclination. A reflection sheet 12 is attached tothe bottom surface and inclined surfaces of the bottom case 10, in orderto reflect light irradiated from each lamp 40 toward the liquid crystalpanel 100. Alternatively, a reflective material may be coated over thebottom surface and inclined surfaces of the bottom case 10.

FIG. 2 is an exploded perspective view for explaining a fasteningprocess for the panel guide 90, support side members 50 and 60, andbottom case 10.

As shown in FIG. 2, the panel guide 90 includes at least one firstfastening portion 140 formed on at least one side surface of the panelguide 90, in order to enable the panel guide 90 to be fastened with thesupport side members 50 and 60, and bottom case 10. The first fasteningportion 140 has a first fastening surface 140 a recessed from the uppersurface of the panel guide 90 in a stepped state, and a first fasteninghole 140 b formed through the first fastening surface 140 a.

Each of the support side members 50 and 60 includes a second fasteningportion 150, which will be fastened to the first fastening portion 140.The second fastening portion 150 has a second fastening surface 150 aprotruded from the surface of the associated support side member 50 or60 in a stepped state such that the second fastening surface 150 acorresponds to the first fastening surface 140 a, a second fasteninghole 150 b formed through the second fastening surface 150 a such thatthe second fastening hole 150 b corresponds to the first fastening hole140 b, and a foreign substance shield 150 c extending inclinedly fromthe second fastening surface 150 a toward the bottom case 10, to preventforeign substance from entering the interior of the liquid crystaldisplay module. One end 15 a of the foreign substance shield 150 c isarranged to be nearer to a light emitting region of the lamps 40 thanthe second fastening hole 150 b. The other end 15 b of the foreignsubstance shield 150 c is inserted into a case hole 160 c provided atthe bottom case 10.

The bottom case 10 includes a third fastening portion 160 formed on atleast one side surface of the bottom case 10, in order to enable thebottom case 10 to be fastened with the first and second fasteningportions 140 and 150. The third fastening portion 160 has a thirdfastening surface 160 a extending from one surface of the bottom case 10to the interior of the liquid crystal display module in a bent statesuch that the third fastening surface 160 a corresponds to the first andsecond fastening surfaces 140 a and 150 a, and a third fastening hole160 b formed through the third fastening surface 160 a such that thethird fastening hole 160 b corresponds to the first and second fasteningholes 140 b and 150 b. The case hole 160 c is also included in the thirdfastening portion 160. The case hole 160 c is formed through one sidesurface of the bottom case 10 such that the foreign substance shield 150c can be inserted into the case hole 160 c.

The fastening portions 140 and 160 of the panel guide 90 and bottom case10 may be formed at four side surfaces, in order to obtain a maximumfastening force.

The corresponding first to third fastening holes 140 b, 150 b, and 160 bare fastened at one time by a screw 200 or the like, as shown in FIG. 3.At the same time, the other end 15 b of the foreign substance shield 150c is inserted into the case hole 160 c of the bottom case 10.

Thus, the assembling process can be simplified because the panel guide90, support side members 50 and 60, and bottom case 10 are fastened atone time by a screw or the like, as described above. Also, it ispossible to prevent metallic foreign substance formed during thefastening of the screw 200 from entering the interior of the liquidcrystal display module, because the foreign substance shield 150 c isfitted in the case hole 160 c of the bottom case 10. Since the fasteningof the screw 200 is achieved through the fastening holes 140 b, 150 b,and 160 b, it is unnecessary to additionally use an insert net for thefastening of the screw 200, as compared to related art's cases.Accordingly, a reduction in material costs is achieved.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

The invention claimed is:
 1. A method for assembling a liquid crystalmodule, comprising: preparing a panel guide that supports a liquidcrystal panel, the panel guide including a first fastening portionhaving a first fastening surface and a first fastening hole, supportside members for holding opposite sides of a lamp irradiating light tothe liquid crystal panel, respectively, each of the support side membersincluding a second fastening portion having a second fastening surface,a second fastening hole corresponding to the first fastening hole, and aforeign substance shield, and a bottom case including a third fasteningportion having a third fastening surface, a third fastening holecorresponding to the first and second fastening holes, and a case holeformed through a side surface of the bottom case, to receive the foreignsubstance shield; aligning the panel guide, the support side members,and the bottom case such that the first to third fastening portionsoverlap; and inserting screws into the first to third fastening holes tofasten the first to third fastening portions by the screws, andinserting the foreign substance shield extending from the secondfastening surface toward the bottom case into the case hole such that anend portion of the screws inserted into the first to third fasteningholes is surrounded by the foreign substance shield, at the same timeinserting screws into the first to third fastening holes.
 2. The methodaccording to claim 1, wherein the first fastening surface is recessedfrom an upper surface of the panel guide in a stepped state; and thefirst fastening hole is formed through the first fastening surface. 3.The method according to claim 2, wherein the second fastening surface isprotruded from an upper surface of the support side member in a steppedstate such that the second fastening surface corresponds to the firstfastening surface; and the second fastening hole is formed through thesecond fastening surface.
 4. The method according to claim 3, whereinthe foreign substance shield has one end nearer to a light emittingregion of the lamp than the second fastening hole, and the other endinserted into the case hole.
 5. The method according to claim 3, whereinthe third fastening surface is extending from the side surface of thebottom case to the lamp in a bent state; and the third fastening hole isformed through the third fastening surface.